Automatic circuit breaker for drying machines and the like



A ril 5, 1927.

' 623,611 J. E. ALEXANDER ET AL AUTOMATIC CIRCUIT BREAKER FOR DRYINGMACHINES AND THE LIKE Original led May 15. -1924 J VEF IQ E I, 5522622A. $262296 I paper "drying machine with one side re- Patented Apr. 5,19217.

UNITED STATES rat-Eur orrics.

JOHN E. ALEXANDER, OF PORT EDWARDS, "NISCQNSIN, AND "STEFHEN A. S'IAEGE,OF PITTSBURGH, PENNSYLVANIA; SAID $TAEGE ASSIGNOR T0 SAID JOHN E.

' ALEXANDER.

nuromarro c'iacurr BREAKER. son DRYING- rmcnrnns AND TIE-IE, LIKE.

Original application filed. May 15, 1924, Serial No. 713,63'7. Dividedand this application filed September.

2, 1925. Serial No. 53,979.

This invention relates to a fabric or paper making machine drier unitand more particularly to an electrically heated drier wherein automaticmeans are provided for breakingthe electric heating circuit when a breakoccurs in the fabric or paper feeding to the drien.

This application is a division of our co-' pending application SerialNo. 713,637, filed Mi1y15, 192 1, to which reference may be had. a v

It is an object of this invention to provide automatic means in anelectrically heated drier unit for rendering the heating elementsinefiective upon the occurrence of a breakin the material feeding to thedrier.

Other and further important objects of this invention will be apparentfrom the disclosures inthe specification and accompanying drawings.

This invention (in a preferredtorm) is illustrated in the drawings andhereinafter more fully described. Y

On the drawings: 7 v Figure 1 is a broken side elevation of a movedillustrating our invention;

Figure 2 is a wiring diagram covering a portion of a single pass of themachine, and

Figure 3 is an enlarged view of our device showing the operation of thesame.

As shown on the drawings:

The paper drier unit comprises a housing 1 having supported therein aplurality of rollers 2 supported on cross-bars 3. En-

gaged on the rollers 2 are a plurality of end less wire mesh or fabricbelts 4 positioned in superimposed relation.

Rigidly mounted within the housing 1 on vertical uprights 5 are aplurality of horizontal members or bars 6. Guide rolls 7 are supportedon the horizontal bars 6 and are arranged to permit the belts 4 to passthereover as illustrated.

Mounted upon each horizontal pair of the bars6 are a plurality ofelectric'heaters S which are supported transversely or lengthwise in thehousing. With this arrange: ment one horizontal set of electric heaters8 is positioned between the upper and lower laps of each belt 4 and outof contact therewith.

The electric heaters 8 in each pass or at each next group of heaters inthe same pass com prises the alternate heaters 13. D and F which areconnected in different combinations to the wires 12, 18 and 141 ofanother three phase circuit. The heater B is con The heatnected with thewires 12 and 13'; the heater Dis connected with the'wires 18 andl t; andthe heater F is connected withthe wires 12 and 14. Connected in each ofthe wires 9, 10 and 11 is a magnetic cont-actor 15.

' The three magnetic contactors '15 connected in the wires 9. 10 and 11are positionedto be controlled by an operating coil 16 connected in awire 17 leading to one terminal of a thermostatlS. The wire 17 is alsoconnected at its other end to a line wire or bus bar 19. Another wire 20connects the thermostat 18 with a second line wire or bus bar 21. Asshown in Figure 2 the wire 9 is connected to the bus bar 19. The wire 10is connected with the second bus bar 21 and the wire 11 is connected toa third. bus bar 22. There are three magnetic contactors 23 connected inthe wires 12, 13 and 14 and said contactors are positioned to becontrolled by an operating coil 24 connected in a wire 25 leadinc; toone terminal of a thermostat 26. The wire 25 is also connected at itsother end to the line wire or bus bar 19. Another wire 27 connects thethermostat 26 with the second line wire or bus bar 21. As illustrated inFigure 2 the wire 12 is connected to the bus bar 19. The wire 13 isconnected with the second bus bar 21. and the wire 14 is connected tothe third bus bar 22. A multiple three phase circuit arrangement is thusprovided for each pass of the drying machine afi'ordinp; a plurality ofindependently controlled circuits providing a balanced arrangement witheach phase or bus bar having connccted thereto a substantially equalloadf several heaters to be energized and de-cnergized at frequentintervals so that the mean temperature will be equal to that at whichthe thermostats are set. Inasmuch as each thermostat can be adjusted orsetfor a different temperature, the temperatures tl'iroughout thehousing 1 can he graduated in a manner to produce the best results.

In each pass of the drier unit adjacent heaters 8 are connected todiiferent supply circuits controlled by diiferent contactorsconsequently the heaters in a given pass are not all turned off or on atthe same time as would be the case if they were all connected to onesupply circuit. A gradient temperature may thus be readily maintained inthe drier unit with the highest temperature where the wet web enters thedrier unit and with a lower temperature where the web leaves the drierunit or any desired temperature relations may be maintained.

here is provided for use with the above a device 36 which is adapted tooperate to disconnect the supply of energy to the electrical heatingelements when the web breaks. Said device 36 comprises an insulatedsupport 30, having mounted thereon a pivoted contact member 31 and anadjacent station ary contact member 32 insulated from said member 31 attheir adjacent ends. The member 31 is supported in such a way that itscurved end 33 normally rests on a web 3 1 as said web feeds into thedrier. The drag of said member 31 on said web tends to keep said member31 in contact with said member 32 against the force of a spring 35, asshown in dotted lines in Figure 3. \Vhen the web 34; breaks, however,the spring 85 forces said member 31 away and contact is broken; thusshutting off the current of electricity in the heating elements. This isdesirable because of the time lag in the functioning of the thermostatsunder such conditions.

lVe are aware that many changes may be made, and numerous details ofconstruction may be varied through a wide range without departing fromthe principles of this invention, and we therefore do not purposelimiting the patent granted hereon, otherwise than necessitated by theprior art.

Ve claim as our invention:

1. A. drier unit comprising web conveying means, electrical. heatingmeans adjacent said conveying means and control means for disconnectingsaid heating means upon breakage of the web.

2. LL drier unit comprising web conveying means, electrical heatingmeans for drying the web and means contacting the web for disconnectingsaid heating means upon pronounced change in the normal movement of theweb.

3. The combination with web conveying means of a heated drier housingtl'n'ough which the web is conveyed and means c0ntacting the web inadvance of the housing for shutting off the heat when the web breaks.

l. The combination with web conveying means of a heated drier housingthrough which the web is conveyed and means outside the drier housingfor shutting off the heat when the web breaks.

5. A drier unit comprising web conveying means, electrical heating meansfor drying the web, and a pivotally mounted member contacting the weband adapted to shut off the supply of energy to the heating means uponbreakage of the web.

In testimony whereof we have hereunto subscribed our names.

JOHN E. ALEXANDER. STEPHEN A. STAEGE.

